[linux-block.git] / net / netfilter / nft_cmp.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net>
 *
 * Development of this code funded by Astaro AG (http://www.astaro.com/)
 */

#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/netlink.h>
#include <linux/netfilter.h>
#include <linux/if_arp.h>
#include <linux/netfilter/nf_tables.h>
#include <net/netfilter/nf_tables_core.h>
#include <net/netfilter/nf_tables_offload.h>
#include <net/netfilter/nf_tables.h>

struct nft_cmp_expr {
	struct nft_data		data;
	u8			sreg;
	u8			len;
	enum nft_cmp_ops	op:8;
};

void nft_cmp_eval(const struct nft_expr *expr,
		  struct nft_regs *regs,
		  const struct nft_pktinfo *pkt)
{
	const struct nft_cmp_expr *priv = nft_expr_priv(expr);
	int d;

	d = memcmp(&regs->data[priv->sreg], &priv->data, priv->len);
	switch (priv->op) {
	case NFT_CMP_EQ:
		if (d != 0)
			goto mismatch;
		break;
	case NFT_CMP_NEQ:
		if (d == 0)
			goto mismatch;
		break;
	case NFT_CMP_LT:
		if (d == 0)
			goto mismatch;
		fallthrough;
	case NFT_CMP_LTE:
		if (d > 0)
			goto mismatch;
		break;
	case NFT_CMP_GT:
		if (d == 0)
			goto mismatch;
		fallthrough;
	case NFT_CMP_GTE:
		if (d < 0)
			goto mismatch;
		break;
	}
	return;

mismatch:
	regs->verdict.code = NFT_BREAK;
}

static const struct nla_policy nft_cmp_policy[NFTA_CMP_MAX + 1] = {
	[NFTA_CMP_SREG]		= { .type = NLA_U32 },
	[NFTA_CMP_OP]		= { .type = NLA_U32 },
	[NFTA_CMP_DATA]		= { .type = NLA_NESTED },
};

static int nft_cmp_init(const struct nft_ctx *ctx, const struct nft_expr *expr,
			const struct nlattr * const tb[])
{
	struct nft_cmp_expr *priv = nft_expr_priv(expr);
	struct nft_data_desc desc = {
		.type	= NFT_DATA_VALUE,
		.size	= sizeof(priv->data),
	};
	int err;

	err = nft_data_init(NULL, &priv->data, &desc, tb[NFTA_CMP_DATA]);
	if (err < 0)
		return err;

	err = nft_parse_register_load(tb[NFTA_CMP_SREG], &priv->sreg, desc.len);
	if (err < 0)
		return err;

	priv->op  = ntohl(nla_get_be32(tb[NFTA_CMP_OP]));
	priv->len = desc.len;
	return 0;
}

static int nft_cmp_dump(struct sk_buff *skb,
			const struct nft_expr *expr, bool reset)
{
	const struct nft_cmp_expr *priv = nft_expr_priv(expr);

	if (nft_dump_register(skb, NFTA_CMP_SREG, priv->sreg))
		goto nla_put_failure;
	if (nla_put_be32(skb, NFTA_CMP_OP, htonl(priv->op)))
		goto nla_put_failure;

	if (nft_data_dump(skb, NFTA_CMP_DATA, &priv->data,
			  NFT_DATA_VALUE, priv->len) < 0)
		goto nla_put_failure;
	return 0;

nla_put_failure:
	return -1;
}

union nft_cmp_offload_data {
	u16	val16;
	u32	val32;
	u64	val64;
};

static void nft_payload_n2h(union nft_cmp_offload_data *data,
			    const u8 *val, u32 len)
{
	switch (len) {
	case 2:
		data->val16 = ntohs(*((__be16 *)val));
		break;
	case 4:
		data->val32 = ntohl(*((__be32 *)val));
		break;
	case 8:
		data->val64 = be64_to_cpu(*((__be64 *)val));
		break;
	default:
		WARN_ON_ONCE(1);
		break;
	}
}

static int __nft_cmp_offload(struct nft_offload_ctx *ctx,
			     struct nft_flow_rule *flow,
			     const struct nft_cmp_expr *priv)
{
	struct nft_offload_reg *reg = &ctx->regs[priv->sreg];
	union nft_cmp_offload_data _data, _datamask;
	u8 *mask = (u8 *)&flow->match.mask;
	u8 *key = (u8 *)&flow->match.key;
	u8 *data, *datamask;

	if (priv->op != NFT_CMP_EQ || priv->len > reg->len)
		return -EOPNOTSUPP;

	if (reg->flags & NFT_OFFLOAD_F_NETWORK2HOST) {
		nft_payload_n2h(&_data, (u8 *)&priv->data, reg->len);
		nft_payload_n2h(&_datamask, (u8 *)&reg->mask, reg->len);
		data = (u8 *)&_data;
		datamask = (u8 *)&_datamask;
	} else {
		data = (u8 *)&priv->data;
		datamask = (u8 *)&reg->mask;
	}

	memcpy(key + reg->offset, data, reg->len);
	memcpy(mask + reg->offset, datamask, reg->len);

	flow->match.dissector.used_keys |= BIT_ULL(reg->key);
	flow->match.dissector.offset[reg->key] = reg->base_offset;

	if (reg->key == FLOW_DISSECTOR_KEY_META &&
	    reg->offset == offsetof(struct nft_flow_key, meta.ingress_iftype) &&
	    nft_reg_load16(priv->data.data) != ARPHRD_ETHER)
		return -EOPNOTSUPP;

	nft_offload_update_dependency(ctx, &priv->data, reg->len);

	return 0;
}

static int nft_cmp_offload(struct nft_offload_ctx *ctx,
			   struct nft_flow_rule *flow,
			   const struct nft_expr *expr)
{
	const struct nft_cmp_expr *priv = nft_expr_priv(expr);

	return __nft_cmp_offload(ctx, flow, priv);
}

static const struct nft_expr_ops nft_cmp_ops = {
	.type		= &nft_cmp_type,
	.size		= NFT_EXPR_SIZE(sizeof(struct nft_cmp_expr)),
	.eval		= nft_cmp_eval,
	.init		= nft_cmp_init,
	.dump		= nft_cmp_dump,
	.reduce		= NFT_REDUCE_READONLY,
	.offload	= nft_cmp_offload,
};

/* Calculate the mask for the nft_cmp_fast expression. On big endian the
 * mask needs to include the *upper* bytes when interpreting that data as
 * something smaller than the full u32, therefore a cpu_to_le32 is done.
 */
static u32 nft_cmp_fast_mask(unsigned int len)
{
	__le32 mask = cpu_to_le32(~0U >> (sizeof_field(struct nft_cmp_fast_expr,
					  data) * BITS_PER_BYTE - len));

	return (__force u32)mask;
}

static int nft_cmp_fast_init(const struct nft_ctx *ctx,
			     const struct nft_expr *expr,
			     const struct nlattr * const tb[])
{
	struct nft_cmp_fast_expr *priv = nft_expr_priv(expr);
	struct nft_data data;
	struct nft_data_desc desc = {
		.type	= NFT_DATA_VALUE,
		.size	= sizeof(data),
	};
	int err;

	err = nft_data_init(NULL, &data, &desc, tb[NFTA_CMP_DATA]);
	if (err < 0)
		return err;

	err = nft_parse_register_load(tb[NFTA_CMP_SREG], &priv->sreg, desc.len);
	if (err < 0)
		return err;

	desc.len *= BITS_PER_BYTE;

	priv->mask = nft_cmp_fast_mask(desc.len);
	priv->data = data.data[0] & priv->mask;
	priv->len  = desc.len;
	priv->inv  = ntohl(nla_get_be32(tb[NFTA_CMP_OP])) != NFT_CMP_EQ;
	return 0;
}

static int nft_cmp_fast_offload(struct nft_offload_ctx *ctx,
				struct nft_flow_rule *flow,
				const struct nft_expr *expr)
{
	const struct nft_cmp_fast_expr *priv = nft_expr_priv(expr);
	struct nft_cmp_expr cmp = {
		.data	= {
			.data	= {
				[0] = priv->data,
			},
		},
		.sreg	= priv->sreg,
		.len	= priv->len / BITS_PER_BYTE,
		.op	= priv->inv ? NFT_CMP_NEQ : NFT_CMP_EQ,
	};

	return __nft_cmp_offload(ctx, flow, &cmp);
}

static int nft_cmp_fast_dump(struct sk_buff *skb,
			     const struct nft_expr *expr, bool reset)
{
	const struct nft_cmp_fast_expr *priv = nft_expr_priv(expr);
	enum nft_cmp_ops op = priv->inv ? NFT_CMP_NEQ : NFT_CMP_EQ;
	struct nft_data data;

	if (nft_dump_register(skb, NFTA_CMP_SREG, priv->sreg))
		goto nla_put_failure;
	if (nla_put_be32(skb, NFTA_CMP_OP, htonl(op)))
		goto nla_put_failure;

	data.data[0] = priv->data;
	if (nft_data_dump(skb, NFTA_CMP_DATA, &data,
			  NFT_DATA_VALUE, priv->len / BITS_PER_BYTE) < 0)
		goto nla_put_failure;
	return 0;

nla_put_failure:
	return -1;
}

const struct nft_expr_ops nft_cmp_fast_ops = {
	.type		= &nft_cmp_type,
	.size		= NFT_EXPR_SIZE(sizeof(struct nft_cmp_fast_expr)),
	.eval		= NULL,	/* inlined */
	.init		= nft_cmp_fast_init,
	.dump		= nft_cmp_fast_dump,
	.reduce		= NFT_REDUCE_READONLY,
	.offload	= nft_cmp_fast_offload,
};

static u32 nft_cmp_mask(u32 bitlen)
{
	return (__force u32)cpu_to_le32(~0U >> (sizeof(u32) * BITS_PER_BYTE - bitlen));
}

static void nft_cmp16_fast_mask(struct nft_data *data, unsigned int bitlen)
{
	int len = bitlen / BITS_PER_BYTE;
	int i, words = len / sizeof(u32);

	for (i = 0; i < words; i++) {
		data->data[i] = 0xffffffff;
		bitlen -= sizeof(u32) * BITS_PER_BYTE;
	}

	if (len % sizeof(u32))
		data->data[i++] = nft_cmp_mask(bitlen);

	for (; i < 4; i++)
		data->data[i] = 0;
}

static int nft_cmp16_fast_init(const struct nft_ctx *ctx,
			       const struct nft_expr *expr,
			       const struct nlattr * const tb[])
{
	struct nft_cmp16_fast_expr *priv = nft_expr_priv(expr);
	struct nft_data_desc desc = {
		.type	= NFT_DATA_VALUE,
		.size	= sizeof(priv->data),
	};
	int err;

	err = nft_data_init(NULL, &priv->data, &desc, tb[NFTA_CMP_DATA]);
	if (err < 0)
		return err;

	err = nft_parse_register_load(tb[NFTA_CMP_SREG], &priv->sreg, desc.len);
	if (err < 0)
		return err;

	nft_cmp16_fast_mask(&priv->mask, desc.len * BITS_PER_BYTE);
	priv->inv = ntohl(nla_get_be32(tb[NFTA_CMP_OP])) != NFT_CMP_EQ;
	priv->len = desc.len;

	return 0;
}

static int nft_cmp16_fast_offload(struct nft_offload_ctx *ctx,
				  struct nft_flow_rule *flow,
				  const struct nft_expr *expr)
{
	const struct nft_cmp16_fast_expr *priv = nft_expr_priv(expr);
	struct nft_cmp_expr cmp = {
		.data	= priv->data,
		.sreg	= priv->sreg,
		.len	= priv->len,
		.op	= priv->inv ? NFT_CMP_NEQ : NFT_CMP_EQ,
	};

	return __nft_cmp_offload(ctx, flow, &cmp);
}

static int nft_cmp16_fast_dump(struct sk_buff *skb,
			       const struct nft_expr *expr, bool reset)
{
	const struct nft_cmp16_fast_expr *priv = nft_expr_priv(expr);
	enum nft_cmp_ops op = priv->inv ? NFT_CMP_NEQ : NFT_CMP_EQ;

	if (nft_dump_register(skb, NFTA_CMP_SREG, priv->sreg))
		goto nla_put_failure;
	if (nla_put_be32(skb, NFTA_CMP_OP, htonl(op)))
		goto nla_put_failure;

	if (nft_data_dump(skb, NFTA_CMP_DATA, &priv->data,
			  NFT_DATA_VALUE, priv->len) < 0)
		goto nla_put_failure;
	return 0;

nla_put_failure:
	return -1;
}


const struct nft_expr_ops nft_cmp16_fast_ops = {
	.type		= &nft_cmp_type,
	.size		= NFT_EXPR_SIZE(sizeof(struct nft_cmp16_fast_expr)),
	.eval		= NULL,	/* inlined */
	.init		= nft_cmp16_fast_init,
	.dump		= nft_cmp16_fast_dump,
	.reduce		= NFT_REDUCE_READONLY,
	.offload	= nft_cmp16_fast_offload,
};

static const struct nft_expr_ops *
nft_cmp_select_ops(const struct nft_ctx *ctx, const struct nlattr * const tb[])
{
	struct nft_data data;
	struct nft_data_desc desc = {
		.type	= NFT_DATA_VALUE,
		.size	= sizeof(data),
	};
	enum nft_cmp_ops op;
	u8 sreg;
	int err;

	if (tb[NFTA_CMP_SREG] == NULL ||
	    tb[NFTA_CMP_OP] == NULL ||
	    tb[NFTA_CMP_DATA] == NULL)
		return ERR_PTR(-EINVAL);

	op = ntohl(nla_get_be32(tb[NFTA_CMP_OP]));
	switch (op) {
	case NFT_CMP_EQ:
	case NFT_CMP_NEQ:
	case NFT_CMP_LT:
	case NFT_CMP_LTE:
	case NFT_CMP_GT:
	case NFT_CMP_GTE:
		break;
	default:
		return ERR_PTR(-EINVAL);
	}

	err = nft_data_init(NULL, &data, &desc, tb[NFTA_CMP_DATA]);
	if (err < 0)
		return ERR_PTR(err);

	sreg = ntohl(nla_get_be32(tb[NFTA_CMP_SREG]));

	if (op == NFT_CMP_EQ || op == NFT_CMP_NEQ) {
		if (desc.len <= sizeof(u32))
			return &nft_cmp_fast_ops;
		else if (desc.len <= sizeof(data) &&
			 ((sreg >= NFT_REG_1 && sreg <= NFT_REG_4) ||
			  (sreg >= NFT_REG32_00 && sreg <= NFT_REG32_12 && sreg % 2 == 0)))
			return &nft_cmp16_fast_ops;
	}
	return &nft_cmp_ops;
}

struct nft_expr_type nft_cmp_type __read_mostly = {
	.name		= "cmp",
	.select_ops	= nft_cmp_select_ops,
	.policy		= nft_cmp_policy,
	.maxattr	= NFTA_CMP_MAX,
	.owner		= THIS_MODULE,
};
Commit	Line	Data
d2912cb1	1	// SPDX-License-Identifier: GPL-2.0-only
96518518	2	/*
ef1f7df9	3	* Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net>
96518518	4	*
96518518 PM	5	* Development of this code funded by Astaro AG (http://www.astaro.com/)
	6	*/
	7
	8	#include <linux/kernel.h>
	9	#include <linux/init.h>
	10	#include <linux/module.h>
	11	#include <linux/netlink.h>
	12	#include <linux/netfilter.h>
8819efc9	13	#include <linux/if_arp.h>
96518518 PM	14	#include <linux/netfilter/nf_tables.h>
96518518 PM	15	#include <net/netfilter/nf_tables_core.h>
c9626a2c	16	#include <net/netfilter/nf_tables_offload.h>
96518518 PM	17	#include <net/netfilter/nf_tables.h>
	18
	19	struct nft_cmp_expr {
	20	struct nft_data data;
4f16d25c	21	u8 sreg;
96518518 PM	22	u8 len;
	23	enum nft_cmp_ops op:8;
	24	};
	25
10870dd8 FW	26	void nft_cmp_eval(const struct nft_expr *expr,
	27	struct nft_regs *regs,
	28	const struct nft_pktinfo *pkt)
96518518 PM	29	{
	30	const struct nft_cmp_expr *priv = nft_expr_priv(expr);
	31	int d;
	32
e562d860	33	d = memcmp(&regs->data[priv->sreg], &priv->data, priv->len);
96518518 PM	34	switch (priv->op) {
	35	case NFT_CMP_EQ:
	36	if (d != 0)
	37	goto mismatch;
	38	break;
	39	case NFT_CMP_NEQ:
	40	if (d == 0)
	41	goto mismatch;
	42	break;
	43	case NFT_CMP_LT:
	44	if (d == 0)
	45	goto mismatch;
954d8297	46	fallthrough;
96518518 PM	47	case NFT_CMP_LTE:
	48	if (d > 0)
	49	goto mismatch;
	50	break;
	51	case NFT_CMP_GT:
	52	if (d == 0)
	53	goto mismatch;
954d8297	54	fallthrough;
96518518 PM	55	case NFT_CMP_GTE:
	56	if (d < 0)
	57	goto mismatch;
	58	break;
	59	}
	60	return;
	61
	62	mismatch:
a55e22e9	63	regs->verdict.code = NFT_BREAK;
96518518 PM	64	}
	65
	66	static const struct nla_policy nft_cmp_policy[NFTA_CMP_MAX + 1] = {
	67	[NFTA_CMP_SREG] = { .type = NLA_U32 },
	68	[NFTA_CMP_OP] = { .type = NLA_U32 },
	69	[NFTA_CMP_DATA] = { .type = NLA_NESTED },
	70	};
	71
	72	static int nft_cmp_init(const struct nft_ctx ctx, const struct nft_expr expr,
	73	const struct nlattr * const tb[])
	74	{
	75	struct nft_cmp_expr *priv = nft_expr_priv(expr);
341b6941 PNA	76	struct nft_data_desc desc = {
	77	.type = NFT_DATA_VALUE,
	78	.size = sizeof(priv->data),
	79	};
96518518 PM	80	int err;
96518518 PM	81
341b6941	82	err = nft_data_init(NULL, &priv->data, &desc, tb[NFTA_CMP_DATA]);
fa5950e4 FW	83	if (err < 0)
fa5950e4 FW	84	return err;
96518518	85
4f16d25c	86	err = nft_parse_register_load(tb[NFTA_CMP_SREG], &priv->sreg, desc.len);
d07db988 PM	87	if (err < 0)
	88	return err;
	89
	90	priv->op = ntohl(nla_get_be32(tb[NFTA_CMP_OP]));
96518518 PM	91	priv->len = desc.len;
	92	return 0;
	93	}
	94
7d34aa3e PS	95	static int nft_cmp_dump(struct sk_buff *skb,
7d34aa3e PS	96	const struct nft_expr *expr, bool reset)
96518518 PM	97	{
	98	const struct nft_cmp_expr *priv = nft_expr_priv(expr);
	99
b1c96ed3	100	if (nft_dump_register(skb, NFTA_CMP_SREG, priv->sreg))
96518518 PM	101	goto nla_put_failure;
	102	if (nla_put_be32(skb, NFTA_CMP_OP, htonl(priv->op)))
	103	goto nla_put_failure;
	104
	105	if (nft_data_dump(skb, NFTA_CMP_DATA, &priv->data,
	106	NFT_DATA_VALUE, priv->len) < 0)
	107	goto nla_put_failure;
	108	return 0;
	109
	110	nla_put_failure:
	111	return -1;
	112	}
	113
ff4d90a8 PNA	114	union nft_cmp_offload_data {
	115	u16 val16;
	116	u32 val32;
	117	u64 val64;
	118	};
	119
	120	static void nft_payload_n2h(union nft_cmp_offload_data *data,
	121	const u8 *val, u32 len)
	122	{
	123	switch (len) {
	124	case 2:
ffb3d9a3	125	data->val16 = ntohs(((__be16 )val));
ff4d90a8 PNA	126	break;
ff4d90a8 PNA	127	case 4:
ffb3d9a3	128	data->val32 = ntohl(((__be32 )val));
ff4d90a8 PNA	129	break;
ff4d90a8 PNA	130	case 8:
ffb3d9a3	131	data->val64 = be64_to_cpu(((__be64 )val));
ff4d90a8 PNA	132	break;
	133	default:
	134	WARN_ON_ONCE(1);
	135	break;
	136	}
	137	}
	138
c9626a2c PNA	139	static int __nft_cmp_offload(struct nft_offload_ctx *ctx,
	140	struct nft_flow_rule *flow,
	141	const struct nft_cmp_expr *priv)
	142	{
	143	struct nft_offload_reg *reg = &ctx->regs[priv->sreg];
ff4d90a8	144	union nft_cmp_offload_data _data, _datamask;
c9626a2c PNA	145	u8 mask = (u8 )&flow->match.mask;
c9626a2c PNA	146	u8 key = (u8 )&flow->match.key;
ff4d90a8	147	u8 data, datamask;
c9626a2c	148
a5d45bc0	149	if (priv->op != NFT_CMP_EQ \|\| priv->len > reg->len)
c9626a2c PNA	150	return -EOPNOTSUPP;
c9626a2c PNA	151
ff4d90a8 PNA	152	if (reg->flags & NFT_OFFLOAD_F_NETWORK2HOST) {
	153	nft_payload_n2h(&_data, (u8 *)&priv->data, reg->len);
	154	nft_payload_n2h(&_datamask, (u8 *)&reg->mask, reg->len);
	155	data = (u8 *)&_data;
	156	datamask = (u8 *)&_datamask;
	157	} else {
	158	data = (u8 *)&priv->data;
	159	datamask = (u8 *)&reg->mask;
	160	}
	161
	162	memcpy(key + reg->offset, data, reg->len);
	163	memcpy(mask + reg->offset, datamask, reg->len);
c9626a2c	164
2b3082c6	165	flow->match.dissector.used_keys \|= BIT_ULL(reg->key);
c9626a2c PNA	166	flow->match.dissector.offset[reg->key] = reg->base_offset;
c9626a2c PNA	167
8819efc9 PNA	168	if (reg->key == FLOW_DISSECTOR_KEY_META &&
	169	reg->offset == offsetof(struct nft_flow_key, meta.ingress_iftype) &&
	170	nft_reg_load16(priv->data.data) != ARPHRD_ETHER)
	171	return -EOPNOTSUPP;
	172
a5d45bc0	173	nft_offload_update_dependency(ctx, &priv->data, reg->len);
c9626a2c PNA	174
	175	return 0;
	176	}
	177
	178	static int nft_cmp_offload(struct nft_offload_ctx *ctx,
	179	struct nft_flow_rule *flow,
	180	const struct nft_expr *expr)
	181	{
	182	const struct nft_cmp_expr *priv = nft_expr_priv(expr);
	183
	184	return __nft_cmp_offload(ctx, flow, priv);
	185	}
	186
ef1f7df9 PM	187	static const struct nft_expr_ops nft_cmp_ops = {
ef1f7df9 PM	188	.type = &nft_cmp_type,
96518518	189	.size = NFT_EXPR_SIZE(sizeof(struct nft_cmp_expr)),
96518518 PM	190	.eval = nft_cmp_eval,
	191	.init = nft_cmp_init,
	192	.dump = nft_cmp_dump,
b2d30654	193	.reduce = NFT_REDUCE_READONLY,
c9626a2c	194	.offload = nft_cmp_offload,
ef1f7df9 PM	195	};
ef1f7df9 PM	196
6b772053 FW	197	/* Calculate the mask for the nft_cmp_fast expression. On big endian the
	198	* mask needs to include the upper bytes when interpreting that data as
	199	* something smaller than the full u32, therefore a cpu_to_le32 is done.
	200	*/
	201	static u32 nft_cmp_fast_mask(unsigned int len)
	202	{
	203	__le32 mask = cpu_to_le32(~0U >> (sizeof_field(struct nft_cmp_fast_expr,
	204	data) * BITS_PER_BYTE - len));
	205
	206	return (__force u32)mask;
	207	}
	208
cb7dbfd0 PM	209	static int nft_cmp_fast_init(const struct nft_ctx *ctx,
	210	const struct nft_expr *expr,
	211	const struct nlattr * const tb[])
	212	{
	213	struct nft_cmp_fast_expr *priv = nft_expr_priv(expr);
cb7dbfd0	214	struct nft_data data;
341b6941 PNA	215	struct nft_data_desc desc = {
	216	.type = NFT_DATA_VALUE,
	217	.size = sizeof(data),
	218	};
cb7dbfd0 PM	219	int err;
cb7dbfd0 PM	220
341b6941	221	err = nft_data_init(NULL, &data, &desc, tb[NFTA_CMP_DATA]);
fa5950e4 FW	222	if (err < 0)
fa5950e4 FW	223	return err;
cb7dbfd0	224
4f16d25c	225	err = nft_parse_register_load(tb[NFTA_CMP_SREG], &priv->sreg, desc.len);
d07db988 PM	226	if (err < 0)
	227	return err;
	228
	229	desc.len *= BITS_PER_BYTE;
d07db988	230
5f48846d PS	231	priv->mask = nft_cmp_fast_mask(desc.len);
5f48846d PS	232	priv->data = data.data[0] & priv->mask;
cb7dbfd0	233	priv->len = desc.len;
5f48846d	234	priv->inv = ntohl(nla_get_be32(tb[NFTA_CMP_OP])) != NFT_CMP_EQ;
cb7dbfd0 PM	235	return 0;
	236	}
	237
c9626a2c PNA	238	static int nft_cmp_fast_offload(struct nft_offload_ctx *ctx,
	239	struct nft_flow_rule *flow,
	240	const struct nft_expr *expr)
	241	{
	242	const struct nft_cmp_fast_expr *priv = nft_expr_priv(expr);
	243	struct nft_cmp_expr cmp = {
	244	.data = {
	245	.data = {
	246	[0] = priv->data,
	247	},
	248	},
	249	.sreg = priv->sreg,
	250	.len = priv->len / BITS_PER_BYTE,
5f48846d	251	.op = priv->inv ? NFT_CMP_NEQ : NFT_CMP_EQ,
c9626a2c PNA	252	};
	253
	254	return __nft_cmp_offload(ctx, flow, &cmp);
	255	}
	256
7d34aa3e PS	257	static int nft_cmp_fast_dump(struct sk_buff *skb,
7d34aa3e PS	258	const struct nft_expr *expr, bool reset)
cb7dbfd0 PM	259	{
cb7dbfd0 PM	260	const struct nft_cmp_fast_expr *priv = nft_expr_priv(expr);
5f48846d	261	enum nft_cmp_ops op = priv->inv ? NFT_CMP_NEQ : NFT_CMP_EQ;
cb7dbfd0 PM	262	struct nft_data data;
cb7dbfd0 PM	263
b1c96ed3	264	if (nft_dump_register(skb, NFTA_CMP_SREG, priv->sreg))
cb7dbfd0	265	goto nla_put_failure;
5f48846d	266	if (nla_put_be32(skb, NFTA_CMP_OP, htonl(op)))
cb7dbfd0 PM	267	goto nla_put_failure;
	268
	269	data.data[0] = priv->data;
	270	if (nft_data_dump(skb, NFTA_CMP_DATA, &data,
	271	NFT_DATA_VALUE, priv->len / BITS_PER_BYTE) < 0)
	272	goto nla_put_failure;
	273	return 0;
	274
	275	nla_put_failure:
	276	return -1;
	277	}
	278
	279	const struct nft_expr_ops nft_cmp_fast_ops = {
	280	.type = &nft_cmp_type,
	281	.size = NFT_EXPR_SIZE(sizeof(struct nft_cmp_fast_expr)),
	282	.eval = NULL, /* inlined */
	283	.init = nft_cmp_fast_init,
	284	.dump = nft_cmp_fast_dump,
b2d30654	285	.reduce = NFT_REDUCE_READONLY,
c9626a2c	286	.offload = nft_cmp_fast_offload,
cb7dbfd0 PM	287	};
cb7dbfd0 PM	288
23f68d46 PNA	289	static u32 nft_cmp_mask(u32 bitlen)
	290	{
	291	return (__force u32)cpu_to_le32(~0U >> (sizeof(u32) * BITS_PER_BYTE - bitlen));
	292	}
	293
	294	static void nft_cmp16_fast_mask(struct nft_data *data, unsigned int bitlen)
	295	{
	296	int len = bitlen / BITS_PER_BYTE;
	297	int i, words = len / sizeof(u32);
	298
	299	for (i = 0; i < words; i++) {
	300	data->data[i] = 0xffffffff;
	301	bitlen -= sizeof(u32) * BITS_PER_BYTE;
	302	}
	303
	304	if (len % sizeof(u32))
	305	data->data[i++] = nft_cmp_mask(bitlen);
	306
	307	for (; i < 4; i++)
	308	data->data[i] = 0;
	309	}
	310
	311	static int nft_cmp16_fast_init(const struct nft_ctx *ctx,
	312	const struct nft_expr *expr,
	313	const struct nlattr * const tb[])
	314	{
	315	struct nft_cmp16_fast_expr *priv = nft_expr_priv(expr);
341b6941 PNA	316	struct nft_data_desc desc = {
	317	.type = NFT_DATA_VALUE,
	318	.size = sizeof(priv->data),
	319	};
23f68d46 PNA	320	int err;
23f68d46 PNA	321
341b6941	322	err = nft_data_init(NULL, &priv->data, &desc, tb[NFTA_CMP_DATA]);
23f68d46 PNA	323	if (err < 0)
	324	return err;
	325
	326	err = nft_parse_register_load(tb[NFTA_CMP_SREG], &priv->sreg, desc.len);
	327	if (err < 0)
	328	return err;
	329
	330	nft_cmp16_fast_mask(&priv->mask, desc.len * BITS_PER_BYTE);
	331	priv->inv = ntohl(nla_get_be32(tb[NFTA_CMP_OP])) != NFT_CMP_EQ;
	332	priv->len = desc.len;
	333
	334	return 0;
	335	}
	336
	337	static int nft_cmp16_fast_offload(struct nft_offload_ctx *ctx,
	338	struct nft_flow_rule *flow,
	339	const struct nft_expr *expr)
	340	{
	341	const struct nft_cmp16_fast_expr *priv = nft_expr_priv(expr);
	342	struct nft_cmp_expr cmp = {
	343	.data = priv->data,
	344	.sreg = priv->sreg,
	345	.len = priv->len,
	346	.op = priv->inv ? NFT_CMP_NEQ : NFT_CMP_EQ,
	347	};
	348
	349	return __nft_cmp_offload(ctx, flow, &cmp);
	350	}
	351
7d34aa3e PS	352	static int nft_cmp16_fast_dump(struct sk_buff *skb,
7d34aa3e PS	353	const struct nft_expr *expr, bool reset)
23f68d46 PNA	354	{
	355	const struct nft_cmp16_fast_expr *priv = nft_expr_priv(expr);
	356	enum nft_cmp_ops op = priv->inv ? NFT_CMP_NEQ : NFT_CMP_EQ;
	357
	358	if (nft_dump_register(skb, NFTA_CMP_SREG, priv->sreg))
	359	goto nla_put_failure;
	360	if (nla_put_be32(skb, NFTA_CMP_OP, htonl(op)))
	361	goto nla_put_failure;
	362
	363	if (nft_data_dump(skb, NFTA_CMP_DATA, &priv->data,
	364	NFT_DATA_VALUE, priv->len) < 0)
	365	goto nla_put_failure;
	366	return 0;
	367
	368	nla_put_failure:
	369	return -1;
	370	}
	371
	372
	373	const struct nft_expr_ops nft_cmp16_fast_ops = {
	374	.type = &nft_cmp_type,
	375	.size = NFT_EXPR_SIZE(sizeof(struct nft_cmp16_fast_expr)),
	376	.eval = NULL, /* inlined */
	377	.init = nft_cmp16_fast_init,
	378	.dump = nft_cmp16_fast_dump,
b2d30654	379	.reduce = NFT_REDUCE_READONLY,
23f68d46 PNA	380	.offload = nft_cmp16_fast_offload,
	381	};
	382
0ca743a5 PNA	383	static const struct nft_expr_ops *
0ca743a5 PNA	384	nft_cmp_select_ops(const struct nft_ctx ctx, const struct nlattr const tb[])
cb7dbfd0	385	{
cb7dbfd0	386	struct nft_data data;
341b6941 PNA	387	struct nft_data_desc desc = {
	388	.type = NFT_DATA_VALUE,
	389	.size = sizeof(data),
	390	};
cb7dbfd0	391	enum nft_cmp_ops op;
23f68d46	392	u8 sreg;
cb7dbfd0 PM	393	int err;
	394
	395	if (tb[NFTA_CMP_SREG] == NULL \|\|
	396	tb[NFTA_CMP_OP] == NULL \|\|
	397	tb[NFTA_CMP_DATA] == NULL)
	398	return ERR_PTR(-EINVAL);
	399
cb7dbfd0 PM	400	op = ntohl(nla_get_be32(tb[NFTA_CMP_OP]));
	401	switch (op) {
	402	case NFT_CMP_EQ:
	403	case NFT_CMP_NEQ:
	404	case NFT_CMP_LT:
	405	case NFT_CMP_LTE:
	406	case NFT_CMP_GT:
	407	case NFT_CMP_GTE:
	408	break;
	409	default:
	410	return ERR_PTR(-EINVAL);
	411	}
	412
341b6941	413	err = nft_data_init(NULL, &data, &desc, tb[NFTA_CMP_DATA]);
cb7dbfd0 PM	414	if (err < 0)
	415	return ERR_PTR(err);
	416
23f68d46	417	sreg = ntohl(nla_get_be32(tb[NFTA_CMP_SREG]));
71df14b0	418
23f68d46 PNA	419	if (op == NFT_CMP_EQ \|\| op == NFT_CMP_NEQ) {
	420	if (desc.len <= sizeof(u32))
	421	return &nft_cmp_fast_ops;
	422	else if (desc.len <= sizeof(data) &&
	423	((sreg >= NFT_REG_1 && sreg <= NFT_REG_4) \|\|
	424	(sreg >= NFT_REG32_00 && sreg <= NFT_REG32_12 && sreg % 2 == 0)))
	425	return &nft_cmp16_fast_ops;
	426	}
71df14b0	427	return &nft_cmp_ops;
cb7dbfd0 PM	428	}
cb7dbfd0 PM	429
4e24877e	430	struct nft_expr_type nft_cmp_type __read_mostly = {
ef1f7df9	431	.name = "cmp",
cb7dbfd0	432	.select_ops = nft_cmp_select_ops,
96518518 PM	433	.policy = nft_cmp_policy,
96518518 PM	434	.maxattr = NFTA_CMP_MAX,
ef1f7df9	435	.owner = THIS_MODULE,
96518518	436	};